Grinding-mill.



L. D. BLACKBURN.

GRINDING MILL.

APPLICATION man OCT. 23. 1915.

Patented May 16, 1916.

3 SHEETS-SHEET I.

Zac$5urw THE COLUMBIA PLANUGRAPH co., WASHINGTON, n. c.

L. D. BLACKBURN.

GRINDING MILL.

APPLICATION FILED on. 23, I915.

Patented May 16, 1916.

3 SHEETS-SHEET 2.

L. D; BLACKBURN.

GRINDING MILL.

APPLICATION FILED OCT. 23, 1915.

H8 w i "M 6 Y8 THE COLUMBIA PLANOURKPH'tO WASHINGTON, D. c.

LAWRENCE D. BLACKBURN, OF IDLEWILD, NORTH CAROLINA.

GRINDING-MILL.

Specification of Letters Patent.

Patented May 16, 1915.

Application filed October 23, 1215. Serial No. 57,511.

To all whom it may concern:

Be it known that I, LAWRENCE D. BLACK- BURN, a citizen of the United States, residing at Idlewild, in the county of Ashe and State of North Carolina, have invented certain new and useful Improvements in Grinding-Hills, of which the following 1s a specification.

My invention relates to grinding mills, and particularly to that class of mills in which the burs are disposed vertically.

()ne of my principal objects is to prov de adjustable means for accurately balanclng the bed-stone in a true vertical position, and for supporting the same in said positlon in such amanner that it will automatically adjust itself to the face of the running stone while the mill is at work.

Another object is to provide a mill with means for separating all chaff and dust and dirt from the grain as it is on its way from the hopper to the mill stones.

Still another object is to provide adjustable means for accurately regulating the quantity of grain fed from the hopper to the burs within a given time.

Other objects will appear in the subjoined description.

An important feature of the invention consists in means specially adapted for adjustment to bring the balancing point of the bed-stone into the plane of the center of gravity of said stone.

Generally speaking, the invention consists in certain novel parts and combinations of parts, as will. be hereinafter described and claimed. reference being had to the accompanying drawings which form a part of this application, and in which Figure 1 is a side elevation of my improved mill, with the uppermost position of the hopper shown in dotted lines; the cleaning fan and the divided shaft operating the same being also shown in dotted lines. Fig. 2 is a front elevation of the mill; with the cleaning fan and the parts connected directly therewith, shown in dotted lines. Fig. 3 is a perspective view of the mill showing the stationary stone and the portion of the frame supporting the same, removed from the other stone and its supporting frame. Fig. 4: is a sectional view of the turn-key employed in regulating the feed mechanism of the mill. Fig. 5 is a perspective of the bed-stone frame, with the stone removed therefrom. Fig. 6 is a rear view of the bedstone. Fig. 7 is a side elevation thereof. Fig. 8 is a perspective of one of the flanged tracks carried by the bedstone frame for supporting the bed-stone;

Fig. 9 is a front elevation of the bed-stone with its supporting attachments secured at its sides; opposite sides of the bed-stone frame and the supporting tracks carried thereby being shown in dotted lines. Fig. 10 is a side view of the reciprocating lever employed in connection with the shoe. Fig. 1.1,is a perspective view showing the two parts of the adjustable balancing device which is secured at each side of the bedstone, the parts being shown separated from each other in the view; and,Fig. 12 is a side elevation of the cleaning fan and the divided shaft which operates it, a portion of the shaft at its coupling being shown in section.

The numeral 1 indicates two parallel sills upon which the mill is mounted. The main frame of the millthe part carrying the two stonesis formed of two frames, separable from each other, but normally held together, which frames are indicated by the numerals 2 and 3; the-former carrying the rotary stone 4L, and the latter, the bedstone 5; said parts having in their meeting faces circular recesses 6 and 7 respectively for the. reception of said stones, which recesses are adapted to register with each other when thetwo cooperating frames are brought together. The frame 2 which carries the revolving stone is provided at each side about midway between its top and bot tom, with an eye-bolt 8 securely held in position by a nut 9. Pivoted to the inner ends of these eye-bolts are the bolts lOhaving the nuts 11 at their free ends, and these bolts 10 are adapted to be passed laterally into the horizontal grooves 12 in the sides of the bed-stone frame 3, which grooves are in alinement with the eye-bolts 8 in the cooperating frame 2. From this arrangement it will be seen that the frames 2 and 3 may be easily locked in rigid engagement with each other by swinging the bolts 10 into the grooves 12 and giving the nuts 11 a few turns: and that they may also be quickly disengaged from each other when it is desired to gain access to the stones or for other reasons. The revolving stone i is rigidly secured to the main shaft 13 to revolve therewith, and this shaft is suitably mounted (at a distance from its inner end and at the rear side of the stone) in the frame 2, and at its outer end in the post or standard 14 at the rear end of the sills 1. This shaft extends centrally through the aperture 6 of the frame 2 supporting the stone 4 in said aperture, and has its inner end projecting in advance of the face of said stone a distance approximately equal to the thickness of the bed-stone. On this projecting inner end 13 of the shaft 13 is a spiral 15 having sufficient frictional engagement with said end to rotate therewith, the purpose of which will be explained hereafter. Mounted on the shaft 13 is the belt pulley 16 adapted to be driven from any suitable source of power.

The bed-stone 5 is suitably held centrally of the aperture 7 in the frame 3, by means that will be hereafter particularly described. This stone has a steel plate 17 secured to its rear side, and at the center of this plate is a struck-out portion having at its base an inclined part 17"", and above this an upwardly extending part 17 approximately parallel with the rear face of the stone. The opening in the steel plate formed by the struck-out portion just referred to, coincides with the central opening 18 of the bed-stone 5, which opening is of a size to loosely receive the spiral 15 on the projecting end 13 of the main shaft 13.

Projecting centrally into the recess 7 of the frame 3 from the outer, or forward side of said fame, is a threaded adjusting bolt 19 having on its outer end a wheel 20 (Figs. 1 and The inner end of this bolt is adapted to engage the portion 17 of the plate 17 to adjust the bed-stone relatively to the rotary stone.

Extending down through the bed-stone frame 3 from the top thereof is the vertical feed-pipe 21, having at its top and emptying thereinto the funnel 22. This feed pipe, as will be seen from Fig. 5, extends down close to the rear face of the bed-stone in approximate parallelism therewith, and terminates just above the portion 17 of the plate 17, so that grain descending through the pipe 21 will strike the inclined section 17 of the plate and be deflected into the opening 18 of the bed-stone where it is at once engaged by the spiral 15 and drawn inwardly till it is caught between the two stones and ground, after which it is expelled through the spout 15* which is suitably held between the cooperating frames 2 and 3.

The portions 17 and 17 just referred to may, if desired, have angular side sections which extend inwardly toward the stone to close the sides of the space between said sections andthe stone, to prevent the possibility. of any of the grain fed from the vertical pi e 21 to the stones, from flying out at said sides. The interior of the vertical pipe 21 is intersected by the horizontally inclined pipe 23 (Figs. 2 and 5). At the end of this latter pipe and inclosed within the bed-stone frame 3 is a fan 24 adapted to'force a blast of air through this pipe to act upon the grain as it is fed to the burs through the vertical pipe 21, and by this means remove from the grain any chaff or light dirt of any kind that may have still been left remaining in it. This fan is driven by a shaft which is formed in two parts 25 and 26 provided with a coupling arrangement at their meeting ends, the part 25 being mounted in the frame 3 and the part 26 in the frame 2. The part 25 terminates in a reduced squared portion 25*, and the part 26 terminates in an enlarged portion 26 having a squared aperture 26 adapted to easily receive said squared end 25. Said reduced end 25 projects beyond the inner face of the frame 3 in such position that when the frames 2 and 3 are brought together, said end enters the squared aperture 26 of the other section of the shaft, and thus the two sections are coupled together. The outer end of the section 26 of the fan shaft projects beyond the rear side of the frame 2 (Fig. 1), and on this projecting portion is rigidly mounted a driving pulley 27 for the fan.

The bed-stone frame 3 is provided at the upper portion of its outer side with a re movable section 3 normally held in position on the frame by screws (as clearly illustrated in Fig. 2), and adapted to give easy access to the fan 24 and the pipes 21 and 23 when desired. This removable section is provided with two air-intake openings 3 for the fan.

An adjusting screw 28 provided with a hand wheel is mounted in the end post 1 1 in alinement with the shaft 13 and has engagement with the end of said shaft, whereby longitudinal adjustment may be imparted to said shaft to move the revolving stone 4- into closer engagement with the bedstone when desired. Hence from this and from what has already been stated, it is seen that either stone may be adjusted relatively to the other.

At the upper rear side of the frame 2 is the post 29, and mounted on the top of the frame in advance of said post are the two 1 and rest upon the upper inturned ends 30 of the standards 30, which ends have a downward curve adapted to receive the rod 31. The hopper is provided on opposite sides with two spring catches 31 which yieldingly engage the supporting frame 31 to hold the hopper thereon when it is found necessary for any reason to tilt the hopper into its vertical position as illustrated in Fig. 1. The post 29 has in its upper end a transverse pivot 29* on which is mounted the reciprocating lever 32 illustrated in Fig. 10. This lever is formed of an upper part 32 and a lower part 32 disposed at an angle to each other and connected together by an integral loop 32 which is so bent as to form the circular opening 33 through which the pivot 29 passes. The section 32 of this lever terminates in an integral ball 34, while the section 32* is provided at its lower end with an opening 35.

The shoe 36 is interposed between the hopper and the feed funnel 22, and is mounted on a horizontal bar 37. The rear end of this bar is pivotally connected with the lower end of the reciprocating lever 32 by means of a pivot 38 which passes through the opening 35 of said lever. The forward end of this shoe is provided with a hook 39, and the hopper frame 31 is provided on its forward side with a hook 40 approximately just above the hook 39, while the turn-key 41 (fully illustrated in Fig. 4) is rotatably mounted at the top of the front side of the bed-stone frame 3 and is provided with a diametrical opening 41*. A cord or cable 42 is connected at one end to the hook 39 of the shoe, is passed over the hook 40 of the hopper frame, and has its other end secured to the turn-key 41 after being passed through the diametrical opening 41 thereof. From this arrangement it will be seen that the shoe 36 is entirely supported by the reciprocating lever 32 at its rear end and the cable 42 at its forward end. It also becomes apparent that when the turn-key 41 is turned in a direction to shorten the cable 42 that the forward end of the shoe 36 will be elevated, thereby lessening the inclination of the bottom of said shoe while at the same time bringing said bottom up closer to the opening in the bottom of the hopper, both of which will serve to retard the passage of the grain from the shoe to the funnel, while on the other hand turning the key 41 in a direction to unwind the cable from around the same and thus lengthen the cable, will serve to lower the forward end of the shoe, thereby increasing the inclination of its bottom, and in turn causing the grain to feed more rapidly from the shoe to the funnel, as the shoe is reciprocated back and forth horizontally by the lever 32 which lever is operated as follows: At the rear side of the mill is the vertical link 43 suitably connected at its upper end with the ball 34 of the lever 32 to form a ball-and-socket joint, and at its lower end pivotally connected with an eccentric strap 44 mounted on an eccentric 45 carried by the main shaft 13 of the mill. In this way it will be seen that when the main shaft is rotated by the pulley 16, the link 43 will be moved up and down imparting its motion to the free end of the section 32 of the reciproeating lever, and causing the lower end of the other section 32 of said lever to reciprocate horizontally, which motion is imparted to the shoe 36 by its supporting bar 37.

Now comes the description of a very important feature of my invention to which special attention is called; namely, the adjustable means for balancing and supporting the bedstone, to cause the same to automatically adjust itself to the running stone as the latter revolves. The bed-stone frame 3 having the central recess 7 for the reception of the stone is provided on diametrically opposite sides of said recess with two horizontally disposed tracks 46, which have the flanges 46 with the openings 47 for securing said tracks to said frame. The bed-stone 5 is provided at diametrically opposite sides thereof with adjustable means for supporting and balancing the stone on the tracks 46; and as a convenient means for attaching said adjusting means to the stone 5, I surround the stone with a tight-fitting band 48. At diametrically opposite sides of this band the clips 49 are rigidly secured thereto extending transversely of the periphery of the band. Each of these clips is formed with a central portion 50 which merges at its top and bottom sides into parallel curved portions 51 which are bent toward each other. The central portion 50 of the clip is provided with any suitable number of openings 52 for riveting or otherwise rigidly securing the clips to the band 48, or if preferred, directly to the stone itself without the intervention of the band. The adjustable slide 53 is adapted to be received into the clip 49, being formed of the central portion 54 which merges at its top and bottom sides into the parallel curved portions 55 which are bent toward each other. At the end of the slide the curved portions 55 thereof merge into the narrow upwardly and downwardly extending finger sections 56 which are bent from each other and occupy a plane approximately parallel to the main section 54 of the slide; while at the center of the slide said curved portions 55 merge into the two track-engaging sections 57 which project outwardly approximately at right angles to the main portion 54 of the slide, and are near enough to each other to permit them to be received between the two opposed inner edges of the curved sections 51 of the clip. Whenever desired these track-engaging sections 57 may be slightly spread at their outer ends, or inclined from each other, as indicated in Fig. 6, which inclination of these supports 57 will cause the jar of the stone to always tend to center it accurately as between the two tracks, and will thus serve a useful purpose where the tracks have, through inadvertence or other reason been spaced slightly farther apart than they should be, leaving too much space for possible lateral play of the stone. At their bases the finger sections 56 and the track-engaging sections are preferably spaced a short distance from each other. When the slide is passed into the clipthe curved sections 55 of the slide are received at the outer side of said sections 51 the clip, while the fingers 56 of the slide are received at the outer side of said section 51 of the clip, the main section 53 of the slide being received inside the clip in easy engagement with the main section 50 thereof, and in approximate parallelism therewith. The main section 53 of the slide is provided at a point in its longitudinal center with a set screw 58, which passes through said section and is adapted to abut against the main section 50 of the clip to lock the clip and slide together when they are brought into the desired adjustment relatively to each other.

In operation it will be seen that by moving the slide 58 longitudinally in the clip, the track engaging sections 57 of the slide which support the stone on the tracks, can be brought into the exact plane of t 1e center of gravity of the stone, thereby giving the stone a perfect balance in a vertical plane, and when the stone is thus balanced the slide is locked in engagement with the clip by means of the set screw 48. 7 When the plane of the center of gravity of the stone is shifted relatively to the supports 57, by reason of wear and tear upon the face of the stone, all that is necessary to restore it again to a perfect balance is to loose the set screws 4E8 and move the slides slightly rearward. As the sections 57 loosely engage the tracks L6, the stone is practically capable of universal movement, and hence is adapted to automatically adjust itself to every different position which the face of the other stone may assume as it rotates on its shaft. The operation of the other parts of the mill have already been explained in the foregoing description.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent is 1. A balancing device for the bed-stone of a grinding mill, comprisin supports for the stone; a band rigidly secured in flat engagement with the periphery of the stone and means secured to the band at opposite sides of the stone for holding the stones upon said supports, said means being adjustable in a direction at right angles to the face of the stone.

2. A balancing device for the bed-stone of a grinding mill, comprising supports for the stone; a band rigidly secured in flat en-' gagement with the periphery of the stone and means secured to the periphery of the band at opposite sides thereof for pivotally holding the stone upon said supports, said means being adjustable transversely of the periphery of the band to bring said pivot points into the plane of the center of gravity of the stone.

3. A balancing device for the bed-stone of a grinding mill, comprising supporting tracks at opposite sides of the stone; clips held on the periphery of the stone at diametrically opposite sides thereof and extending transversely of said periphery; slides received into said clips and adapted to move longitudinally therein; projections on said slides adapted to pivotally engage said tracks; and means for locking the slides in adjusted position on the clips.

4. In grinding mills, the combination with the bed-stone of a supporting frame therefor provided with a recess for receiving the stone; parallel tracks secured to said frame at horizontally opposite sides of said recess, said tracks being arranged to face toward each other and extending in a direction at right angles to the face of the stone; clips secured to the periphery of the stone at horizontally opposite sides of its center and extending transversely of said periphery; slides received into said clips and provided with upper and lower projections adapted to receive the tracks between them to pivotally support the stone upon the tracks, said slides being adapted for longitudinal adjustment in the clips to bring the supporting pivots into the plane of the center of gravity of the stone; and means for locking the slides in adjusted engagement with the clips.

5. In grinding mills, a bed-stone having a metallic plate rigidly secured to the back thereof with a struck-out portion at its center forming an opening in the plate leading into the central opening of the bedstone, said struck-out portion being bent to form an inclined section at its bottom and an approximately vertical section above the inclined section, the vertical section being spaced at its upper end from the bed-stone, vertical side sections extending inwardly from said first named vertical section to the bed-stone; a supporting frame for the bedstone provided with a recess into which the stone is received; and a feedpipe for conveying the grain to the central opening of the stone, said pipe extending down through the frame into said recess close to the rear side of the stone and terminating centrally above the space between the stone and the upper ends of said vertical sections of the metallic plate, whereby grain descending through the pipe will fall upon the inclined bottom of the struck-out portion of the plate and be deflected into the central opening of the stone. 1

6. A balancing device for the bed-stone of a mill, comprising supporting tracks spaced from the stone at opposite sides thereof; outwardly extending supports held on the stone at horizontally opposite sides thereof for pivotally supporting the stone upon said tracks, said supports being inclined upwardly from their inner ends toward their outer ends, to cause the jar of the stone to tend to center the same between the two tracks.

In testimony whereof I affix my signature in presence of two witnesses.

LAWRENCE D. BLACKBURN. Witnesses:

A. R. VAIL, Honn E. ELLER.

@opiea of this patent may be obtained for five cents each, by addressing the Commissioner of Patents,

Washington, D. 0." 

